Bacterial cell permeability study by metal oxide and mixed metal oxide nanoparticles: analysis of the factors contributing to the antibacterial activity of nanoparticles

Biopolymer based nanoparticles and their therapeutic potential in wound healing - A review

Nanoparticles (NPs) have been extensively investigated for their potential in nanomedicine. There is a significant level of enthusiasm about the potential of NPs to bring out a transformative impact on modern healthcare. NPs can serve as effective wound dressings or delivery vehicles due to their antibacterial and pro-wound-healing properties. Biopolymer-based NPs can be manufactured using various food-grade biopolymers, such as proteins, polysaccharides, and synthetic polymers, each offering distinct properties suitable for different applications which include collagen, polycaprolactone, chitosan, alginate, and polylactic acid, etc. Their biodegradable and biocompatible nature renders them ideal nanomaterials for applications in wound healing. Additionally, the nanofibers containing biopolymer-based NPs have shown excellent anti-bacterial and wound healing activity like silver NPs. These NPs represent a paradigm shift in wound healing therapies, offering targeted and personalized solutions for enhanced tissue regeneration and accelerated wound closure. The current review focuses on biopolymer NPs with their applications in wound healing.

Synthesis and characterization of polysiphonia/cerium oxide/nickel oxide nanocomposites for the removal of toxins from contaminated water and antibacterial potential

Due to massive industrial development, organic and inorganic wastes are very common in most industrial effluents from the pharmaceutical industry. Even in low concentrations, they are very dangerous and harmful to humans and other living organisms. Antibiotics are frequently detected in surface waters, in soil, in wastewater from sewage treatment plants, and even in drinking water. The major environmental threat they pose has prompted to search for effective and environmentally friendly means of eliminating these toxins. The biogenic synthesis of nanomaterials using natural herbal extracts has attracted considerable attention due to their low-cost, environmentally friendly and non-toxic nature, and as a reversal of various physical and chemical processes. The ceria nanoparticles (CeO2 NPs), nickel oxide nanoparticles (NiO NPs), and CeO2/NiO nanocomposites (CeO2/NiO NCS) were successfully prepared by simple biosynthetic routes using Polysiphonia urceolata algae extract as green surfactants and tested for toxic ofloxacin removal efficiency. The formed nanostructures were identified and characterized by various microscopic (FESEM-EDX, TEM, XRD, BET, and XPS) and spectroscopic (UV-Vis, FTIR, and TGA) methods. The adsorption/desorption of ofloxacin (OFX) on the surface of the nanomaterials was investigated under optimized conditions (initial dose 20 mg/L, agitation speed 250 rpm, pH 12, adsorbent dose 0.5 mg/L, and contact time 120 min). The removal efficiencies were 78%, 86%, and 94% for CeO2 NPs, NiO NPs and CeO2/NiO NCS, respectively, where OFX removal was found to be spontaneous, followed by Freundlich isotherm and pseudo-second order kinetic reaction model. The OFX adsorption mechanism on the nanomaterials involved the surface complexation via specific electrostatic attraction and H-bonding. The biogenic nanomaterials were also tested for their antibacterial activity against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus epidermidis and Staphylococcus aureus. The CeO2/NiO NCS exhibited the highest antibacterial activity with zone of inhibition (31.12 ± 0.59 mm) against S. epidermidis, followed by CeO2NPs and NiONPs with zones of inhibition (25.53 ± 1.2 mm) and (21.42 ± 0.6 mm) against P. aeruginosa and S. epidermidis, respectively. This study demonstrated the efficiency of the synthesized nanomaterials in removing toxins such as OFX from contaminated water and can serve as potential antibacterial and antioxidant agents. Notably, the heterogeneous nanomaterials demonstrated remarkable stability across a broad pH range, promising reusability and indicated tremendous potential of waste biomass reduction and OFX effluent treatment.